Advertisement

Induction of Incoordinate Synthesis of Muscle Proteins by the Tumor Promoter TPA and the Carcinogen EMS

  • H. Holtzer
  • S. Forry-Schaudies
  • P. Antin
  • G. Dubyak
  • V. Nachmias
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 182)

Abstract

Combined cytoimmunofluorescent, electron microscopic, and biochemical studies have repeatedly demonstrated the following about normal myogenesis: (1) That the switch in differentiation programs from replicating presumptive myoblasts to their daughter postmitotic myoblasts occurs prior to fusion; (2) That this switch requires DNA synthesis, but not cytokinesis; (3) That 6–12 hours after their last mitosis, both daughter definitive myoblasts initiate the coordinate synthesis of muscle-specific myosin heavy and light chains, tropomyosin, C-protein and M-band protein and at about this time become fusion competent. This switch in differentiation programs also involves the initiation of the synthesis of the muscle-specific intermediate filament protein, desmin; (4) That this sequence of events begins in chick myotomes at stages 14–15 and in chick limb buds at stages 20–21; (5) That there is a lag phase of hours between the earliest detection of these muscle-specific isoforms in mononucleated postmitotic myoblasts and their assembly into myofibrils. During this lag period, myofibrillar proteins and desmin appear to be widely distributed throughout the sarcoplasm.

Keywords

Normal Medium Myofibrillar Protein Identical Field Nonmuscle Myosin Synthetic Pattern 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • H. Holtzer
    • 1
  • S. Forry-Schaudies
    • 1
  • P. Antin
    • 1
  • G. Dubyak
    • 1
  • V. Nachmias
    • 1
  1. 1.Departments of Anatomy and Biochemistry-BiophysicsUniversity of Pennsylvania Medical SchoolPhiladelphiaUSA

Personalised recommendations